Apparatus for applying pigments to surfaces



Oct. 29, 1935.

C. A. WULF AT PARATUS FOR APPLYING PIGMENTSV TO SURFACES Filed vApril 16, 1954 Fvg. 1 if zz I I I INVENTOR. y/vaziefl Wu lj;

ATTORNEYS Patented Oct. 29, i935 STATES Arsr @FICE crasse APPARATB FOB APPLYING PIGMENTS 111i SURFACES v charla A. wan, Indianapolis, ma., mimmto The c Process Company, Beaver Falls,

The object of my invention is to provide improved means for applying patterned colors to surfaces. My improvements relate particularly to the application of frits to enameled sheet metal surfaces but are not limited to that ileld.

The invention resides in an improved screen stencil wherein the screen frame is effectively resilient transversely of the. plane of the screen.

The accompnyin drawing illustrates my invention.

Fig. 1 is a vertical section of my improved screen supported in operative position over a receiving plate and ilexed as in use; and

, Fig. 2 a perspective, on a smaller scale, of the l5 screen.

In the drawing i0, I0 indicate the side bars and I l, il the end bars of a screen frame to which the stencil screen l2 is secured.

'I'he side bars I0. i0 are made of highly resilient 2 0 material and are relatively thin so as to be readily flexed transversely of their thickness, but are sufiently wide to be rigid against stresses width- The end bars are preferably reasonably rigid transversely of their thickness.

'I'he screen -I2 is stretched tightly across and secured at its edges to the frame and this screen is preferably of metal wire and fine mesh, in which case it is soldered or brazed to metal frame One end bar l I is provided with means, such as pins Il. I2, to which frame supporting springs I4, Il may be attached, said pins also serving as frame anchors by projecting into vertically u slotted brackets Il, II upon which springs Il are suspended.

,The screen I2 may be. photographically sensitized, exposed, developed and washed into a desired stencil or blocking elements applied thereto in any well known manner to form a desired stencil.

Whensoprepareditisplacedcverthepiste 20, to which ink or frit is tobe applied, with one end suspended by springs il and the other end so supported that, when the spring-supported end is depressed the screen may be brought to close parallelism with plate 20. 5

Ink or frit 2| being applied to the upper face of the screen near its spring-supported end, a squeegee 22. presseddownwardly and drawn toward the other end of the screen, serves to propel the ink or frit across the screen and through l0 its permeable portions onto plate 20.

In order that the screen I2 may have a long life it is desirable that distortion from the plane of the frame be avoided as much as possible and therefore squeegee 22 is provided at each end l5 with a shoev or roller 2l which will engage the side bars il in the line of the squeegee and serve to ilex said bars progressively against the action of springs Il. Consequently, as the squeegee pro- Agresses away from'the spring supported end of 20 the frame said end is raised higher and higher away from the plane of plate 20 thus stripping the screen away from the applied ink immediately back of the squeegee soastoleave asharplydenned deposit sunk. es

If the frame is sufficiently long relative t0 medial placed permeable portion of the screen both ends of the framemay be vertically fixed and the flexibility of the side bars depended upon to produce the proper stripping action.

I claim as my invention:

1. A screen stencil comprising a screen and a supporting frame, two opposite sides of said frame being substantially resilient to stresses normal to the plane of the screen.

2. A stencil of the character speciiied in claim l arranged above a receiving surface and supported at one end by yielding means normally acting to raise said end away from the receiving surface. 0

CHARLES A. WULP. 

